Abstract: An alternator includes a body portion housing a charging circuit. A voltage regulator is mounted to the body portion and electrically coupled to the charging circuit. The voltage regulator is configured and disposed to output at least one charging current. An isolator is mounted to the body portion and electrically coupled to the charging circuit and the voltage regulator. The isolator is configured and disposed to be electrically coupled to at least two batteries with the isolator independently passing the at least one charging current to each of the first and second batteries.

Abstract: By employing a single phase pulse width modulated inverter system, a-c power line voltage may be effectively converted to single phase, variable amplitude and frequency sinusoidal voltage for driving a single phase a-c induction motor at an adjustable speed. The motor may be driven directly in response to the power line voltage (such as during start-up or when it is desired to run the motor at the power line frequency) by bypassing the inverter system and connecting the motor across the power line. Reduced energy consumption may be obtained by operating the motor in response to a reduced inverter output frequency. Switching the motor from the power line to the inverter, and vice versa, is accomplished without interruption. Immediately prior to each, switchover the inverter output voltage is synchronized to the power line voltage to minimize any electrical disturbance during the switching transition.

Abstract: A multizone air conditioning system for cooling multiple zones by circulating refrigerant in a closed circuit through the system. The system includes control means for activating and deactivating at least one individual evaporator unit and means for retaining within the portion of the tubing of an individual evaporator unit, when and if it deactivated, an amount of refrigerant which is approximately equal to the amount of refrigerant in the individual evaporator unit when it is activated. As a result, the refrigerant in the system remains balanced regardless of whether individual evaporator units are activated or deactivated.

Abstract: A control system for an electric domestic water heater operatively associated with an external heat source, such as a heat pump, and including a water storage tank having an internal electric heater unit controlled by a tank thermostat responsive to the water temperature in the tank. The control system maintains the tank heater unit effectively turned off and turns the external heat source on in response to an indication from the tank thermostat that there is a demand for hot water. The control system turns the external heat source off in response to an indication from the tank thermostat that the demand for hot water has been satisfied. The control system may include devices, such as an evaporator thermostat, high pressure cut-out switch, etc., indicative of the condition of the external heat source for turning the external heat source off, turning the tank heater unit on and maintaining the tank heater unit on until the demand for hot water has been satisfied.

Abstract: A control system for an electric water heater operatively associated with an external heat source, such as a heat pump. The water heater includes a water storage tank provided with an electric tank heating unit having a tank thermostat which closes in response to water temperature in the tank, allowing a flow of current through the tank heating unit so as to turn it on to heat the water, and which opens when the tank thermostat has been satisfied, interrupting the current flow so as to turn the tank heating unit off. The control system as responsive to the initial current surge through the tank heating unit when the tank thermostat closes to (1) interrupt the current flow to the tank heating unit so as to maintain the heating unit off and (2) to turn on the external heat source and maintain it on until the tank thermostat opens. The initial current surge cleans the contacts of the tank thermostat by burning off any insulating oxide residues which may have formed on them.

Abstract: A heat pump system in which the compressor speed is varied in response to load conditions by a programmed control system and the indoor coil fan speed, during heating operations, is proportioned to compressor speed as further modified by the outdoor air temperature.